October 22, 2011

DARPA Hopes To Retrieve, Reuse Components From Dead Satellites

by editor

The U.S. Defense Advanced Research Projects Agency (DARPA) has announced a new program that would recycle parts from non-functioning satellites to help save money when constructing replacement satellites, various media outlets reported Friday.

According to Andrew Tarantola of Gizmodo, DARPA's Phoenix system "consists of a primary Tender/Servicer satellite and multiple smaller mini-satellites called 'Satlets.' As the plan goes, after the Tender has reached geosynchronous orbit (GEO), the Satlets are launched aboard a commercial communications satellite from which the Tender will collect them and store them on-board itself."

In a Thursday press release, DARPA officials said that they believe there is more than $300 billion worth of satellites in GEO, some 22,000 miles above the Earth's surface. Of those, many have been retired and place in a so-called "graveyard" orbit.

Even so, the military organization believes that these craft contain several valuable component parts, including antennas, which could be retrieved and re-used to cut the costs of producing new or replacement satellites.

Antennas are of particular interest, Evan Ackerman of Dvice reports, because of their size. Ackerman says that Phoenix would harvest antennas and other functional parts from retired satellites, then would assemble the parts together to form a new, working module.

"One major hurdle is that satellites out that far in space were not launched with the expectation that it would ever be possible to service them," he added. "So, they're not exactly easy to take apart, meaning that any harvester system will need to be able to cut through metal casings and rip out subsystems that were never intended to be ripped out. It'll probably all be done through telepresence, with a human on the ground directly controlling the appendages and tools on the harvester satellite."

In a statement, DARPA program manager David Barnhart admits that achieving success with the program won't be easy.

"Satellites in GEO are not designed to be disassembled or repaired, so it´s not a matter of simply removing some nuts and bolts,” he said. "This requires new remote imaging and robotics technology and special tools to grip, cut, and modify complex systems, since existing joints are usually molded or welded."

"Another challenge is developing new remote operating procedures to hold two parts together so a third robotic 'hand' can join them with a third part, such as a fastener, all in zero gravity," Barnhart added. "For a person operating such robotics, the complexity is similar to trying to assemble via remote control multiple Legos at the same time while looking through a telescope."

However, the potential payoff could be enormous. Tarantola called it "a brilliant idea," and DARPA Director Regina E. Dugan said, "If this program is successful, space debris becomes space resource."